the festival is expected to draw hundreds of thousands of people to the city over three days. charles clifford has details. >> reporter: this stage is constructed completely with our crew. sherry sternberg helped start the festival 12 years ago. thursday, she and an army of roadies were putting the final touches on the stages and venues >> we've got most of the audio and staging up, a lot of signage still needs to get it. >> reporter: it starts on friday with a kids' day then opens up to the general public on saturday and sunday from 11:00 to 7:00. there are six stage, and each day will feature dozens of acts, all free. last year, 750,000 people showed up over three days. this is happening on a very busy weekend here in the bay area and that has added an extra challenge for organizers, specifically in how people will get to the park. >> with all of the other things going on, i just want there to be safety concerns with regards to public transportation, respecting the neighborhoods, that's a big priority for us, that people leave this event and everyone has a good time. >> take